Arc-lamp electrode.



UNITE STATES PATENT OFFICE.

WILLIAM R. irorr, or Lnxnwoon, orrro, AssIGNon, BY MESNE hssIGNMENrs, 'ro

NATIONAL CARBON COMPANY, me, A CORPORATION or NEW YORK.

Ana-Lamar ELECTRODE.

Specification of Letters Patent. v Patented Oct. 23, 1917.

No Drawing. Continuation of application Serial No. 863,463, filed September 25, 1914. This application filed February 28, 1916. Serial No. 80,887.

To all whom it may concern:

Be it known that I, WILLIAM R. Mo'rr, a citizen'of the United States, residing at Lakewood, in the county of Quyahoga and State of Ohio, have invented a certain new and useful Improvement in Arc-Lamp Electrodes, of which the following is a full, clear, and exact description.

My invention relates to are light electrodes for roducing a brilliant white light of high candle power, and is particularly adapted to photographic use.

This application is a continuation of my application Serial No. 863,463, filed September 25, 1914, now patent 1,235,996, Aug. 7,

The highest candle power in commercial arc lights has hitherto been obtained by the use of calcium fluorid as the main constituent, which produces a yellow flame. Yellow flame arcs are well adapted for lighting smoky or foggy places, on account of the great penetrating power of the yellow rays. In certain cases, however, a pure white light is a desideratum, this being particularly true of photographic and photoengraving work. For general street lighting also, a white light is to be preferred.

In making flame electrodes for photographic and photoengraving work, it has been customary to use rare-earth fluorids alone or in combination with other salts instead of using calcium fluorid. Calcium fluorid is considered to be the best all around flaming constituent that can be used in arc lamp electrodes, but the yellow characterof its light has heretofore hindered its use'in photographic lamps. My invention enables me to use calcium fluorid and thus obtain the high candle power incident thereto, while producing a snow white light.

Uranium in the electric are probably gives more lines in the spectrum than any other known element, and the arc is exceptionally rich in the blue. and violet rays, while it also contains a considerable number of ultraviolet rays. Uranium therefore has a unique distinction of giving 50% more photographic power when used in the are, than rare-earth fluorids, or titanium oxid, which have heretofore been considered the materials having the highest photographic values.

Uranium has a great propensity to form various chemical reactions with other substances when incorporated in the arc, and inasmuch as the candle power of the arc increases with the number of chemical compounds that can be formed therein, uranium is a desirable material to be used in elec trodes for this, if for no other reason.

Uranium materials produce an arc hav-' ing an intense blue center rich in actinic properties, and when it is mixed with calcium fluorid in making up an arc;lamp electrode it fully blends with the yellow rays of the latter to produce an intense snow white light of extraordinary photographic power.

In the application referred to above I have disclosed a number of compounds for use in an arc lamp electrode among which are the various oxids of uranium, uranates of calcium, strontium and other metals, metallic uranium, uranium carbid, uranium nitrid, uranium borate, uranium fluorid, uranium oxyfluorid. In addition to these I may use the double fluorids, such as sodium uranium fluorids, potassium uranium fluorider} and barium uranium fluorids, as well as other compounds of uranium and fluorin with other elements. Uranous fluorid (UrF sodium uranium fluorid (NaUrF,) and potassium uranium fluorid (KUrF,) ma be mentioned as particularly favorable. go pounds volatilizing at high temperatures, insoluble in waterand having no inherent objectionable characteristics, are preferable.

The use of uranium salts and materials is not restricted to any definite amounts in proportion to the other materials in the electrode, but merely by way of example it may be stated that in cored electrodes for instance, the paste may consist of about 40% 'core black and flaming material, which may consist entirely of uranium salts, fluorids, oxids or other uranium material. When calcium fluorid is to be used in conjunction with uranium, the proper amount will be used to blend with the uranium rays to produce a snow white light.

Having described my invention, what I 1 claim is 1. An arc lamp electrode containing a fluorin compound of uranium and a conducting body.

2.; Eamp fauerin' mam smm 0.? mium and carbon.

a113, iamp elect-rode containing a, daubie fiuorid of uranium and a conducting bafiy,

An are eiecfii'ode containing s0- 55.11am uranium lucid a condusiiixg @0617.

5. All are lmLp electmda cwtainLa-g urafiuariii. and a nmiucting 1055 electrode containing a w 11:11am, and sarbon.

6. An are lamp electrode contgining calcium :Suorid, a fiuorin compound of uranium, an. a conducting body.

7. [in are lamp electrode containing calcium fiusri a fiuorin compound of ura- ZLn iestimony whereof, 1 hereunto afixmy signature.

WFJLLMVE EE/IQTT. 

